The Third Brake Light (Third Brake Light Service)
August 1, 2021
So you thought you only had two brake lights. Look again and you'll see one in the center at a higher level than the two on either side of the vehicle. They're sometimes in the inside of the vehicle behind the back window, or they could be in the deck lid, on the roof or on the spare wheel carrier,
But why is that third brake on your vehicle? Experts say it helps prevent rear end collisions. Tests done by installing the third brake light in taxis and fleet vehicles showed fewer rear end crashes in the ones that had the extra light. The third brake light was mandated in new passenger cars in 1986 in the US and Canada. The requirement was added to new light trucks and vans in 1994.
Sometimes it's difficult to know if your third brake light is even working. Many vehicles have bulb warning systems that alert you to non-functional bulbs, but not all do. Your vehicle service facility will often check to see if all your turn signals, taillights and headlights are working during routine maintenance inspections, and they may notice that the third brake light is out.
So, do you have to have it replaced? Not necessarily. Many areas only require one brake light to work in the rear of a vehicle. So even though new vehicles have to have the third brake light, you may not get a ticket if it eventually stops working. But you may be missing an opportunity to drive a safer vehicle if you don't get it fixed.
In 1995, an insurance institute study found that 1986 model cars were involved in 5 percent fewer rear-end collisions from 1986-1991 than they would have expected without the extra light.
Ask your service advisor for advice. Keep in mind that in these days of drivers distracted by everything from texting to putting on makeup while driving, you can reasonably conclude that anything that makes you more visible to the vehicle behind you adds one more—possibly life saving—safety margin.
Commerce Auto Repair
9575 Commerce Rd.
Commerce, Michigan 48382
248.363.3749
Need Service?
More articles from Commerce Auto Repair

Keep It Rolling Right
June 14, 2026
Keeping your tires rotated regularly is one of the simplest yet most important maintenance services you can perform on your vehicle. It is where each tire is moved to a different position: front to back, side to side. That rotation helps to ensure your tires wear evenly, which directly impacts sa... More

The Untold Truth About Blinker Fluid: Why Your Car Desperately Needs It
May 10, 2026
If youve been ignoring your dashboard, your mechanic, and that one guy at the gas station who muttered bro your blinkers sound dry, then buckle up because today we dive into the critical world of blinker fluid maintenance. What Is Blinker Fluid? Blinker fluid is a high-viscosity, luminescent com... More

T for Transmission, T for Trouble (Automatic Transmission Trouble Signs)
April 15, 2026
One of the hardest working components of your vehicle is its transmission, shifting gears up and down when you need it to. The transmission is vital to your vehicle driving properly, and if you start to see signs of problems in it, its best to have them fixed earlier rather than later. (Since ne... More
